Privigen

human normal immunoglobulin (IVIg)

About

This is a summary of the European public assessment report (EPAR) for Privigen. It explains how the Committee for Medicinal Products for Human Use (CHMP) assessed the medicine to reach its opinion in favour of granting a marketing authorisation and its recommendations on the conditions of use for Privigen.

Patients who are at risk of infection because they do not have sufficient antibodies (proteins naturally found in the blood that help the body to fight infections and other diseases). These can be people who are born with a lack of antibodies (primary immunodeficiency syndrome, PID). It also includes patients whose lack of antibodies is due to a cancer of the blood (myeloma or chronic lymphoid leukaemia) or children born with acquired immune deficiency syndrome (AIDS), who suffer from frequent infections. These types of conditions are called ‘immunodeficiency syndromes’ and their treatment is called ‘replacement therapy’.

Patients with certain immune disorders. These patients have an abnormal immune system (the body’s defence system) that needs to be adjusted. They comprise patients with idiopathic thrombocytopenic purpura (ITP), who do not have enough platelets (components in the blood that help it to clot) and who are at high risk of bleeding; patients with Guillain-Barré syndrome or chronic inflammatory demyelinating polyneuropathy (CIDP), inflammatory disorders of the nerves that result in muscle weakness and numbness; and patients with Kawasaki disease, a disease mainly seen in children which causes inflammation of blood vessels. This type of treatment is called ‘immunomodulation’ (immune adjustment).

Patients after allogeneic blood-stem-cell transplantation (a complex procedure where the patient receives stem cells from a matched donor to help restore the bone marrow).

Treatment with Privigen as a replacement therapy should be started and monitored by a doctor experienced in treating immunodeficiency syndrome.

Privigen is usually given as an infusion into a vein by a doctor or nurse. The dose and frequency of infusions (how often it is given) depend on the disease being treated. The dose may need to be adjusted for patients depending on their response.

For full details, see the summary of product characteristics (also part of the EPAR).

The active substance in Privigen, human normal immunoglobulin, is a highly purified protein extracted from human plasma (part of the blood). It contains immunoglobulin G (IgG), which is a type of antibody. IgG has been used as a medicine since the 1980s and has a wide range of activity against organisms that can cause infection. Privigen works by restoring abnormally low IgG levels to their normal range in the blood. At higher doses, it can help to adjust an abnormal immune system and modulate the immune response.

As human normal immunoglobulin has been used to treat these diseases for some time, and in accordance with current guidelines, only three small studies were needed to establish the effectiveness and safety of Privigen in patients.

In the first study, Privigen was used as replacement therapy in 80 patients with PID, with the medicine being infused every three or four weeks. The main measure of effectiveness was the number of serious bacterial infections over a year’s treatment.

The second study looked at using Privigen for immunomodulation in 57 patients with ITP. Privigen was given on two consecutive days. The main measure of effectiveness was the highest blood platelet level that was achieved in the week after Privigen was given.

A third study examined the use of Privigen for immunomodulation in 28 patients with CIDP who were given Privigen every three weeks over a period of 24 weeks. The main measure of effectiveness was the number of patients who showed an improvement of at least 1 point on a 10-point scale of disability in their arms and legs.

In the first study, the patients had an average of 0.08 serious infections per year. Since this is below the predefined threshold of one infection per year, this indicates that the medicine is effective as replacement therapy.

In the second study, 46 (81%) of the 57 patients had a platelet count above 50 million platelets per millilitre at least once during the study.

This confirmed that Privigen is effective in immunomodulation.

In the third study, 17 (61%) of the 28 patients responded to treatment with an improvement of at least one point on the disability scale. The average improvement was about 1.4 points.

The most common side effect with Privigen (seen in more than 1 patient in 10) is headache. Some side effects are more likely to occur when using a high rate of infusion, in patients with low immunoglobulin levels, or in patients who have not received Privigen before or for a long time. For the full list of all side effects reported with Privigen, see the package leaflet.

Privigen must not be used in people who are hypersensitive (allergic) to normal human immunoglobulin or any of the other ingredients, or in patients who are allergic to other types of immunoglobulins, especially where they have deficiency (very low levels) of immunoglobulin A (IgA) and they have antibodies against IgA. Privigen must not be used in patients with hyperprolinaemia (a genetic disorder causing high levels of the amino acid proline in the blood).

A risk-management plan has been developed to ensure that Privigen is used as safely as possible. Based on this plan, safety information has been included in the summary of product characteristics and the package leaflet for Privigen, including the appropriate precautions to be followed by healthcare professionals and patients.

Haemolysis (breakdown of red blood cells) is an uncommon side effect in patients given human normal immunoglobulin (occurring with less than 1 dose in 100). Severe haemolysis seems to be slightly more frequent with Privigen than with some other products containing the same active substance. The company that markets Privigen will make some changes in the way it is produced and will carry out a study to monitor the effect of the changes.